pyredir is a flexible but simple redirector for Squid. URLs matching regular expressions can be redirected using regular expression substitution, databases of filename-to-URL mappings, alternative configuration files, or child redirectors. Utilities are provided for generating database files from file archives. It is primarily useful for redirecting requests to large local FTP archives, but it can also be useful as a top-level redirector which separates and feeds requests to more specialized child redirectors.
rocknroll (Rsync fOr baCKup and Roll) is an incremental backup maker based on rsync. It backs up a remote directory tree to a destination directory on the local host. For this backup, it manages a set of archives named tag.1, tag.2, etc. Using the famous "link-dest" option of rsync, it keeps only the difference between the different archives.
Sparse is a semantic parser of source files. It's neither a compiler (although it could be used as a front-end for one) nor a preprocessor (although it contains a preprocessing phase). It is meant to be a small, simple, easy to use library. Its function is to create a semantic parse tree for some arbitrary user for further analysis. It's not a tokenizer, nor is it a generic context-free parser. Context (semantics) is what it's all about: figuring out not just what the grouping of tokens are, but what the types are that the grouping implies.
In Haskell, data type declarations, Parsec parsers, and HughesPJ pretty-printers very much resemble each other; supplying all three is virtuous, but involves a large amount of code duplication. syntran is a code generator designed to reduce the amount of duplication. Its source is similar to a Parsec LanguageDef-using parser, annotated with the unique information from the data type declaration and the pretty-printer which would normally not be found in a parser. It separates this information out to generate pure Haskell.